Device and method for brewing a beverage

ABSTRACT

A capsule holder for receiving a capsule containing tea material is provided, the capsule holder comprising a sidewall having an upper rim, means for supporting the capsule within the capsule holder, so that the capsule partially covers the area inside the upper rim, a filter situated beneath the intended location of the capsule and an openable and closable passage on the opposite side of the filter from the upper rim. A brewing device comprising the capsule holder and a method of brewing a tea-based beverage in the brewing device are also provided.

TECHNICAL FIELD OF THE INVENTION

The present invention relates to a device and a method for brewing abeverage. In particular, the invention relates to infused tea-basedbeverages that are brewed in a device having an infusion chamber.

BACKGROUND TO THE INVENTION

Beverages such as tea and coffee are usually prepared in the home usingground coffee, tea bags or loose-leaf tea. However, the long brewingtime required and the mess that is produced are inconvenient. Thereforebrewing devices have been devised which provide a convenient, rapid andconsumer-friendly way of brewing such beverages. The beverage materialis typically provided in a single use capsule or other container whichis disposed of after brewing the beverage. For coffee beverages thecapsule itself typically functions as the brewing chamber. The volume ofthe capsule is normally less than that of the final beverage, so it isnecessary for the brewing water to flow through the capsule. This isachieved by having a filter in the capsule so that the brewed beveragecan be dispensed whilst the beverage material is retained, and isdisposed of together with the capsule.

This method, however, is not well-suited for brewing tea, as tea leavesrequire a larger volume in which to infuse. Therefore devices forbrewing tea have been designed which have a separate, larger infusionchamber. For example, WO 2007/042485 discloses a device for preparing aninfused beverage, having an infusion container for containing liquid. Acartridge containing tea leaves is introduced into a cavity in thedevice. The bottom part of the cartridge comprises a liquid-permeablefilter. The infusion container and the cavity communicate with eachother, so that when liquid is poured into the infusion container itflows to the cartridge. The tea leaves are thus immersed in the liquidand infusion takes place. After infusion has taken place, a passagecommunicating with the cavity is opened to let the infused liquid flowfrom the infusion container through the cavity and through the filter ofthe cartridge to the passage. The spent tea leaves are collected in thecartridge and are removed from the cavity together with the cartridge.Whilst the infusion chamber allows space for tea leaves to infuse, thismethod has a number of disadvantages. In particular the cartridge mustfirstly provide sufficient area for the filter to allow the beverage tobe dispensed in a short time once brewing has taken place, and secondlyhave sufficient volume to contain the spent tea leaves which swellduring infusion, typically to around four times their dry volume. Thusthe cartridge has to be relatively large. It also has to be sufficientlystrong to support the weight of the spent tea leaves when it is removedfrom the device. Thus a substantial amount of material (e.g. plastic) isrequired to make the capsule. Furthermore, the capsule body and filterare typically made from different materials, so the capsule cannot beeasily recycled. These are both undesirable from the point of view ofcost and also environmental impact. Hence it is an object of the presentinvention to overcome these disadvantages.

BRIEF DESCRIPTION OF THE INVENTION

The present invention solves these problems by locating the filter inthe capsule holder rather than in the capsule. Accordingly, in a firstaspect, the present invention provides a capsule holder for receiving acapsule, the capsule holder comprising:

-   -   a sidewall having an upper rim,    -   means for supporting the capsule within the capsule holder, so        that the capsule partially covers the area inside the upper rim,    -   a filter situated beneath the intended location of the capsule,        and    -   an openable and closable passage on the opposite side of the        filter from the upper rim.

The capsule holder of the invention performs some of the functionsperformed in the prior art by the capsule, such as filtering the brewedbeverage in order to retain the spent tea leaves. Thus the functionalityrequired of the capsule is significantly reduced and the construction ofthe capsule can be much simpler. For example, the capsule no longerneeds to be opened on both sides so it can be a simple, impermeable cupwith a foil lid. This of course requires that there is a route for thebrewed beverage to pass from the infusion chamber to the filter in thecapsule holder. Thus the capsule must not cover the whole of the areainside the upper rim of the capsule holder. Nonetheless, the capsuleholder must support the capsule in place during brewing.

The capsule holder comprises means for supporting the capsule. Thesemeans support the base and/or the flange of the capsule. These means maycomprise one or more protrusions on the inside of the sidewall and/orthe base of the capsule holder. For example, there may be a shelf on theinside of the sidewall just below the upper rim of the capsule holder.Alternatively or additionally, there may be ribs, walls or pillars etcwhich extend upwards from the base.

Alternatively, or additionally, the base itself may be shaped so as tosupport the capsule. The capsule holder preferably further comprisesmeans for defining the location and orientation of the capsule. Thecapsule may have rotational symmetry, in which case the means define anumber of possible orientations. The means for defining the location andorientation of the capsule may comprise protrusions and/or indentationson the shelf.

Preferably, the means for supporting the capsule consists of a shelf onthe inside of the sidewall of the capsule holder. This has the advantagethat there are no ribs, walls or other protrusions on the base orsidewall of the capsule holder which would create locations within thecapsule holder which could trap tea leaves, and hence be difficult toclean.

In a second aspect, the invention provides a strainer which is adaptedto co-operate with a receptacle to form a capsule holder, the strainercomprising:

-   -   a base (73) and a rim (74),    -   means (28) for supporting a capsule (30) within the strainer, so        that the capsule partially covers the area inside the rim, and    -   a filter (25) situated beneath the intended location of the        capsule.

In a third aspect the invention provides a brewing device comprising

-   -   an infusion chamber with a bottom rim which defines an opening;    -   a capsule holder according to the first aspect of the invention;    -   means for moving the capsule holder and/or the infusion chamber        so that the upper rim of the capsule holder is connected to the        bottom rim of the infusion chamber;    -   means for introducing liquid into the capsule so that the liquid        and tea material can mix and flow into the infusion chamber so        as to brew the beverage;    -   a valve for opening the passage in the capsule holder to allow        the beverage to flow from the infusion chamber through the        filter and out through the passage.

In a fourth aspect, the invention provides a method of preparing atea-based beverage in a brewing device according to the second aspect ofthe invention, the method comprising the steps of:

-   -   a) inserting a capsule containing tea material into the capsule        holder;    -   b) connecting the upper rim of the capsule holder to the bottom        rim of the infusion chamber;    -   c) introducing liquid into the capsule and releasing the tea        material from the capsule so that the liquid and tea material        mix and flow into the infusion chamber so as to brew the        beverage;    -   d) after brewing has taken place, opening the passage in the        capsule holder to allow the beverage to flow from the infusion        chamber through the filter and out through the passage.

DETAILED DESCRIPTION OF THE INVENTION

As used herein the term “tea material” refers to tea plant material,herb plant material or a mixture thereof. For the avoidance of doubt,the term “tea material” does not include coffee material. The term “teaplant material” refers to leaf, bud and/or stem material from Camelliasinensis var. sinensis and/or Camellia sinensis var. assamica. The teaplant material may be substantially fermented (i.e. black tea),partially fermented (i.e. oolong tea) or substantially unfermented (i.e.green tea or white tea). It may also be a blend of one or more of theaforementioned tea plant materials. Other ingredients which are commonlyused to flavour leaf tea products may also be combined with the teaplant material (e.g. bergamot, citrus peel and the like). The term “herbplant material” refers to material which is commonly used as a precursorfor herbal infusions. Preferably the herb plant material is selectedfrom chamomile, cinnamon, elderflower, ginger, hibiscus, jasmine,lavender, lemongrass, mint, rooibos (obtained from Aspalathus linearis),rosehip, vanilla and verbena. The tea material may additionally comprisefruit pieces (e.g. apple, blackcurrant, mango, peach, pineapple,raspberry, strawberry etc).

Preferably the tea material is dried and has a moisture content of lessthan 30 wt %, more preferably less than 20 wt % and most preferably from0.1 to 10 wt %. Preferably the tea material particles have a size (i.e.longest diameter) of from about 2 to about 10 mm, preferably 3 to 7 mm.

The term “beverage” refers to a substantially aqueous drinkablecomposition which is suitable for human consumption. Preferably thebeverage comprises at least 85% water by weight of the beverage, morepreferably at least 90% and most preferably from 95 to 99.9%. Preferablythe beverage comprises from 0.04 to 3%, more preferably from 0.06 to 2%,most preferably from 0.1 to 1% by weight tea solids.

The term “brewing” refers to the addition of a liquid, particularly hotwater, to tea material, so that steeping or soaking the tea material inthe liquid releases soluble substances into the liquid (e.g. flavourand/or aroma molecules) thereby to form a beverage. Brewing may becarried out at any temperature, but preferably in the range of 80 to 95°C.

The term “infusion chamber” means a vessel in which infusion of teamaterial takes place, and which is large enough both to allow the teamaterial to move around in the liquid during infusion, and also tocontain a substantial part (i.e. at least 50%) of the volume of thefinal beverage. The term “infusion chamber” therefore does not refer tocapsules inside which brewing takes place, as is typically the case incoffee machines.

The term “capsule” refers to a rigid or semi-rigid container in whichtea material is or may be packaged, for example a capsule, cartridge,pod, or the like.

The present invention will now be described with reference to thefigures, wherein:

FIG. 1 shows a brewing device according to the invention.

FIG. 2 is a schematic diagram showing the main functional components ofthe device.

FIG. 3 shows the device of FIG. 1 with the capsule holder in its loweredposition.

FIG. 4 shows the device as in FIG. 3, now with a capsule inserted intothe capsule holder.

FIG. 5 shows a first embodiment of the capsule holder removed from thedevice.

FIG. 6 shows a second embodiment of the capsule holder removed from thedevice, and containing a capsule.

FIG. 7 shows (a) a side view of a capsule (b) a perspective view of acapsule without a lid and (c) with a lid.

FIG. 8 shows views from above of capsules having various generallyelliptical shaped flanges.

FIG. 9 shows the manifold of the infusion chamber with an opening memberfor opening the lid of the capsule.

FIG. 1 shows one non-limiting embodiment of a brewing device accordingto the invention. The device 1 has a casing 2 with a front side 3 and arear side 4. An infusion chamber 10 and a capsule holder 20 are locatedat the front side of the device. The infusion chamber 10 has a bottomrim 12 which defines an opening in its lower side. The infusion chambermay have an opening in its top side which is covered with a removablelid 15, or it may be constructed as a vessel without an opening in itstop side. The capsule holder 20 is designed to receive a capsule. It islocated in a support 6 and preferably has a handle 22. The capsuleholder is preferably substantially circular when viewed from above,which provides for easy cleaning since there are no corners in which tealeaves could become trapped.

In FIG. 1, the capsule holder 20 is shown in position for brewing, i.e.so that the upper rim 23 of the capsule holder is in water-tight contactwith the bottom rim 12 of the infusion chamber 10. The infusion chamber10 is supported and held in place by a manifold (not shown). A waterreservoir, heater, and pump (not shown) are located inside the rear 4 ofthe casing. At the bottom of the front side 3 of the casing there is atray 8 on which a cup 9 is placed when the beverage is dispensed. Adispensing spout 7 is positioned beneath the capsule holder.

FIG. 2 is a schematic diagram showing the main functional components ofthe device. Water from the reservoir 50 is fed to the infusion chamber10 via a water filter 52, a water pump 54, a heater 56 and a valve 57.The heater is preferably a flow-though heater. The valve 57 controls theroute the water takes between the heater 56 and the infusion chamber 10.For example, the water may firstly be pumped to the infusion chamber 10via the capsule 30 in order to brew a beverage 60. Subsequently, thevalve 57 can re-direct the water such that it enters the brewing chamber10 via a rinse head 18 in order to rinse and/or clean the brewingchamber 10. There may also be an air pump 58 which can pump air to theinfusion chamber, for example via the capsule 30 which is located in thecapsule holder 20, or via the capsule holder itself. The spout 7, cup 9and tray 8 are located beneath the capsule holder 20.

FIG. 3 shows the device of FIG. 1 with the capsule holder 20 lowered sothat its upper rim 23 is separated from the bottom rim 12 of theinfusion chamber. The capsule holder 20 is preferably removable from thesupport 6 so that a capsule can be easily inserted and also for ease ofcleaning. FIG. 4 shows the device with a capsule 30 inserted into thecapsule holder 20, which is in the lowered position.

FIG. 5 shows one embodiment of a capsule holder 20 removed from thedevice: (a) in a perspective view and (b) in cross-section. The capsuleholder 20 has a sidewall 24 with an upper rim 23 and a base 26. Thesidewall 24 is preferably circular when viewed from above.

The capsule holder comprises means 28 for supporting a capsule, suchthat the capsule partially covers the area inside the upper rim. In theembodiment shown in FIG. 5, the means for supporting the capsule 28consist of a shelf 28A on the inside of the sidewall 24 just below theupper rim 23 and ribs 28B extending upwards from the base 26.

A filter 25 is located inside the capsule holder beneath the capsule.Below the filter 25 is a passage 29 through which the beverage flowsduring dispensing and which is closed by a drain valve 21 duringbrewing. The filter preferably consists of a fine mesh made, forexample, of stainless steel, nylon, polyester or PTFE. The mesh sizemust be sufficiently small to catch small pieces of tea material butlarge enough to ensure that draining is not too slow. Preferably, themesh size is from 100 to 500 microns, more preferably 150 to 300microns.

Preferably the filter (when in its normal position in the device) isinclined to the horizontal at an angle of from 5 to 45°, preferably from10 to 30°, such as about 20°. Having the filter at an angle to thehorizontal has two advantages: firstly it presents a larger surfacearea, and hence increases the speed of draining. Secondly tea materialcollects at the bottom of the sloped filter while leaving the upper partclear of tea material so that the beverage drains freely through it.

FIG. 6 shows perspective views of a second embodiment of the capsuleholder 20 which consists of two separable parts, a receptacle 70 and astrainer 72. FIG. 6( a) shows the capsule holder when assembled with acapsule 30 in place, and FIG. 6( b) shows the capsule, strainer andreceptacle separated.

The receptacle 70 has a sidewall 24 and a base 26. Again, the sidewallis preferably circular when viewed from above. Located in the base 26 isa passage 29 through which the beverage flows during dispensing andwhich is closed by a drain valve (not shown) during brewing. Thereceptacle 70 has a handle 22.

The strainer 72 has a base 73, a rim 74 and a handle 75. In theembodiment shown in FIG. 6, the means for supporting the capsulecomprise a shelf 78 on the inside of the sidewall 24 just below the rim74. The shelf 78 extends around part of the sidewall. The capsule 30 hasa flange 33 which corresponds to the shape of the shelf, so that theflange rests on the shelf along substantially all of one side of thecapsule, and thus is supported by it. The sidewall is preferablycircular (when viewed from above), so the shelf similarly has the formof an arc of a circle. This requires the flange of the capsule to begenerally elliptical in shape. In contrast, if the capsule had forexample a circular flange, the area of contact between the shelf and theflange would not be sufficient to support the capsule. Hence and extrasupports would be required inside the capsule holder. These could resultin locations within the capsule holder which could trap tea leaves, andhence be difficult to clean.

It is not essential that the shelf is continuous, provided that it iscapable of supporting the flange of the capsule. Thus for example, theshelf could have small gaps. The width of the shelf preferably matchesthe width of the flange, and is preferably at least 3 mm wide. The part80 of the flange 33 which rests on the shelf 78 is indicated in FIG. 6(a). Small members 71 on the shelf ensure that the capsule is located inthe correct position and in one of the two possible correctorientations.

At least part of the base 73 of the strainer is made up of a filter 25.In the preferred embodiment shown, the part of the base 73 which islocated underneath the capsule is solid whilst the rest of the baseconsists of the filter. The solid part may also serve to support thecapsule. The filter preferably consists of a fine mesh made, forexample, of stainless steel, nylon, polyester or PTFE. The mesh sizemust be sufficiently small to catch small pieces of tea material butlarge enough to ensure that draining is not too slow. Preferably, themesh size is from 100 to 500 microns, more preferably 150 to 300microns.

As shown in FIG. 6( a), in use the strainer 72 rests on the receptacleand is supported by the sidewall 24. The rim 74 of the strainer formsthe upper rim 23 of the capsule holder 20. The strainer covers the wholeof the top of the receptacle 70, so that liquid cannot pass between therim 74 of the strainer and the sidewall 24 of the receptacle, and hencecan only enter the receptacle 70 by passing through the filter. Thefilter prevents spent tea leaves from entering the receptacle 70.Preferably the rim 74 is made from an elastomeric material. Thereby itis in effect a gasket which forms seals both between the receptacle andthe strainer, and also between the capsule holder and the infusionchamber.

This embodiment has the advantage that the strainer and receptacle canbe easily separated for cleaning. Moreover, in order to empty out spenttea leaves from the capsule holder, it is only necessary to remove thestrainer and tip the spent leaves out from it.

Preferably the handle 75 of the strainer is larger than and overlaps thehandle 22 of the receptacle. When the strainer is located in thereceptacle, the handle 75 of the strainer sits on top of handle 22 ofthe receptacle, as shown in FIG. 6( a). This allows the receptacle andstrainer to be picked up together, by gripping them from above andbelow. Nonetheless, the strainer can be easily removed from thereceptacle by gripping the edges of its handle 75 where it extendsbeyond the handle 22 of the receptacle.

The handle 75 of the strainer may optionally have a projection 77 on itslower side, which rests in a corresponding hollow 79 in the top side ofthe handle 22 of the receptacle. This helps to locate the strainercorrectly with respect to the receptacle. The strainer may optionallyhave a lip (not shown) on its rim, for example located opposite thehandle, which rests in a corresponding notch in the top of the sidewallof the receptacle. This helps to locate the strainer correctly withrespect to the receptacle, and also to support it.

FIG. 7( a) shows a side view of a capsule 30. The capsule comprises abody part 31 and a lid 32. The body part 31 defines a cavity 35 in whichthe tea material 36 is placed. The lid is attached to the body part soas to enclose the tea material 36 within the capsule. The functionalityrequired of the capsule is significantly reduced compared to knowncapsules, because the capsule does not need to contain a filter. Thebrewing liquid does not need to enter through one side and exit throughthe other, so there is no need to puncture or otherwise make an openingin the body part of the capsule. Thus the construction of the capsule isgreatly simplified. Thus the body part is preferably a single,impermeable piece and preferably does not contain any means (for examplea filter, or an openable or weakened area) for allowing liquid to enteror exit the capsule through the body part. The body part is preferablymade from plastic or aluminium. It may be formed for example byinjection moulding or by thermoforming.

The cavity 35 is preferably generally circular in cross-section, whenviewed from above, as shown in FIG. 7( b). This shape is convenient fromthe point of view of manufacture and also for filling tea material intothe capsule. It also facilitates release of the tea material from thecapsule during brewing, since there are no corners or other areas wherethe tea material could become trapped. “Generally circular” does notrequire that the cavity has an exactly circular cross-section; thus forexample it could have small indents, provided that there are no narrowrecesses in which tea material could become trapped.

The body part comprises a flange 33, and the lid is attached to theflange, e.g. by heat-sealing, thereby enclosing the tea material. Inorder to provide sufficient area to attach the lid securely, the flangeis preferably at least 3 mm wide. The flange 33 also serves to supportthe capsule in the capsule holder by resting on the shelf on the insideof the sidewall of the capsule holder, as described above. Thus theflange is shaped and sized to match its intended location in the capsuleholder.

The preferred embodiment of the capsule holder described above requiresa capsule with a flange which is generally elliptical in shape.“Generally elliptical” does not require that the flange is exactlyelliptical. The flange has a radius of curvature that is similar to theradius of the inside of the sidewall 24 of the capsule holder, so thatthe shape of the flange generally corresponds to the shelf. Nonetheless,small variations from an elliptical shape can be accommodated whilstthere is still sufficient overlap between the flange and the shelf tosupport the capsule. Some examples of generally elliptical shapes areshown in FIG. 8. In a particularly preferred embodiment, the flange ofthe capsule is defined by two intersecting circular arcs each having aradius of curvature (R) which is substantially the same radius as thecapsule holder, i.e. half of the internal diameter (D) of the capsuleholder, as shown in FIG. 8( b). The ratio of the longest diameter of theflange to the shortest diameter of the flange is from 1.2:1 to 1.5:1. Aminimum ratio of 1.2:1 is required in order to give sufficient space forthe brewed beverage to pass by the capsule, and a maximum ratio of 1.5:1is required so that the capsule is large enough to contain sufficienttea material, without requiring an excessively large capsule holder.

The capsule is preferably symmetrical, and most preferably has 180°rotational symmetry about a vertical axis. Thus the capsule can beplaced in the capsule holder in either of two orientations.

In a preferred embodiment, the body part of the capsule is transparent,so that the tea material inside the capsule is visible. This isattractive to the consumer, and also has the advantage that the contentscan be inspected for quality control purposes after filling usingoptical means, rather than, for example, by weight.

The functionality required of the capsule is significantly reducedcompared to known capsules which contain a filter. There is no need forthe capsule to hold the spent tea leaves, nor does the capsule need toform a water-tight connection with the infusion chamber. In fact, thecapsule is immersed in the brewing liquid. Since the capsule only needsto be large enough and strong enough to contain a single serving of thedry tea material it can be much smaller than known capsules. Thus theinternal volume of the capsule (i.e. the volume of the cavity) is from10 to 24 cm³, preferably 12 to 19 cm³, most preferably from 14 to 18cm³. Moreover, the capsule only needs to be strong enough to support drytea material, and not wet spent tea material. Thus the body part of thecapsule can also have relatively thin walls.

The reduced capsule size means that the amount of material (e.g.plastic) needed to make the capsule is significantly reduced. This hasenvironmental and cost advantages. Furthermore, the capsule body partcan be more easily recycled because it is made of a single material,unlike typical capsules having a filter. A small capsule also has theadvantage of taking up less space during transport and during storage,for example in a consumer's cupboard.

The cavity must not be so shallow that tea material bounces out of itduring filling. Thus the depth of the cavity is preferably at least 10mm, more preferably at least 13 mm. On the other hand, the cavity mustnot be so deep that it is difficult to remove the tea material from thecapsule at the start of brewing. Thus the depth of the cavity ispreferably at most 20 mm, more preferably at most 18 mm. It is easier toremove the tea material from a cavity with a depth in the upper part ofthis range when the volume of the cavity is also towards the upper endof its range (i.e. when the cavity is not both deep and narrow).

The cross-sectional area and diameter of the cavity are related to therequired volume and depth. Consequently, the diameter of the cavity ispreferably from 30 to 45 mm. The lid, which overlaps with or covers theflange as well as covering the cavity, is therefore preferably fromabout 45 to 60 mm in diameter, more preferably 47 to 58 mm. The lid ispreferably shaped to generally match the shape of the flange.

The lid can be a simple thin film or foil. The lid is preferably made ofa metallic foil or a laminated foil, most preferably a laminate ofaluminium foil and polyethylene. In a preferred embodiment, the shape ofthe lid is defined by two intersecting circular arcs, but with truncatedends 38, as shown in FIG. 7( c). The length of the lid between the twotruncated ends is from 47 to 58 mm, and the maximum width of the lid isfrom 45 to 50 mm.

Preferably the lid has perforations in order to facilitate opening thecapsule to inject water and release the tea material, as will bedescribed below. More preferably the lid 32 has a line of perforations34 in the form of a curve, with sections which extend backwards from theends of the curve, as shown in FIG. 7( c). This configuration produces awell-defined opening when the lid is pushed against a blunt openingmember (described below), which allows the tea leaves to be releasedfrom the capsule. Most preferably there are two sets of perforations inthe lid, arranged symmetrically, as shown in FIG. 7( c), so that inwhichever of the two possible orientations the capsule is inserted, oneset of perforations is always located beneath the opening member. Thecut:tie ratio of the perforations should be such that they do not bursttoo easily, for example during transport, but nonetheless open withoutrequiring too great a force. For example, for an aluminiumfoil/polyethylene laminate lid, a cut:tie ratio of around 1:2 issuitable.

Typically the capsules are provided to the consumer in air-tightsecondary packaging, for example as packs containing a number ofcapsules (e.g. ten). Having a perforated lid has a further advantage inthat some of the tea aroma is released from the tea material inside thecapsule into the space inside the secondary packaging. Thus the consumerobtains the aroma of tea on opening the secondary pack.

In use, the device functions as follows. With the capsule holder in itslowered position, the user removes the capsule holder from the support,or in the second embodiment of the capsule holder shown in FIG. 6, theuser may just remove the strainer from the receptacle. A capsulecontaining tea material is placed into the capsule holder so that itrests on the means for supporting the capsule. These means preferablyalso locate the capsule in the correct position and orientation.

The capsule holder is then replaced on the support. Next the user raisesthe support, for example by pressing a button on the device whichactivates an actuator. The capsule holder travels vertically upwardsuntil it connects with the infusion chamber, and forms a water-tightseal. In an alternative embodiment, the infusion chamber could move downtowards the capsule holder.

In the context of the present invention, ‘connecting the upper rim ofthe capsule holder to the bottom rim of the infusion chamber’ and ‘theupper rim is connected to the bottom rim of the infusion chamber’ shouldbe understood to mean that upper rim of the capsule holder and thebottom rim of the infusion chamber form a water-tight contact, so thatthe capsule holder and infusion chamber form a vessel in which thebrewing liquid can be held while brewing takes place. The capsule holderand infusion chamber may be connected by means of an intermediate membersuch as a gasket (for example a ring made of rubber or other compliantmaterial located on the upper rim of the capsule holder and/or thebottom rim of the infusion chamber) in order to provide a good seal. Theinfusion chamber and the capsule holder form a space for brewing whenconnected. Preferably the volume of the space for brewing is at least75%, more preferably at least 90% of the volume of the final beverage.

The device may have means for recognizing a capsule and/or readinginformation from a code associated with the capsule or the capsuleholder. This allows the capsule to be recognized by the device, so thatthe device can automatically set the parameters for the brewingoperation, such as the brewing time, water temperature, pressure, volumeor flow rate, and/or the path(s) the liquid follows within the brewingdevice etc. It also allows the device to be programmed so that it onlyoperates if the correct type of capsule is present. Thus a valid codesignifies that an expected type of capsule is present, and an invalidcode signifies an unexpected type of capsule, a capsule that has alreadybeen used or that no capsule is present. The recognition system can beof any suitable type, such as mechanical interlocking between thecapsule and the capsule holder; optical recognition (e.g. by means ofcolour, fluorescence or bar code), electrical, magnetic, radio-frequencyidentification (RFID) chip etc.

In a preferred embodiment, the recognition system is based on theprinciple of electromagnetic induction and metal detection. The capsuleand/or the capsule holder comprises conductive material having two edgesections which are situated on opposite sides of the cavity, preferablysituated near to or at opposite ends of the flange i.e. near to or atopposite ends of the capsule. A coil carrying an alternating current andlocated in the brewing device close to the capsule induces eddy currentsin conductive material. The eddy currents produce an opposingelectromagnetic flux that changes the impedance of the coil. The changein impedance is a function of the strength and freedom of the eddycurrents to circulate within the conductive material. Discontinuities inthe conductive material constrain and weaken the strength of the eddycurrents and affect the impedance of the coil. Thus the arrangement(e.g. position, shape) of the edge sections of the conductive materialencode information which allows the brewing device to recognise thecapsule according to the configuration of the conductive material. It ispreferred that edge sections are substantially straight-edged sections,and it is particularly preferred that the edge sections are parallel toone another. The edge sections do not need to extend across the entirewidth of the capsule, but in a preferred embodiment they do. Preferredexamples of conductive materials include metallic sheets, metallic foilsand foil laminates.

This method allows near field and non-contact detection recognitionusing a simple coding system over a wide range of physical andelectrical tolerances, and is particularly suitable in instances wherethe brewing device needs to recognise a limited number of codes (i.e.preferably no more than 10 codes). An advantage of this method is thatthe coils do not need to be in physical contact with the conductivematerial. This means that recognition is possible even if there is anon-conductive material between the coil and the conductive material.For this reason, several ways of associating the conductive materialwith the capsule are possible. Furthermore capsule recognition ispossible even if there is water and/or residual tea material between thecoil and the capsule.

Preferably the recognition system comprises: two resonant tank circuits,each one comprising a coil and a capacitor; two electronic detectioncircuits for detecting changes in coil impedance; a means for generatinga signal wherein the signal is indicative of the changes in coilimpedance; and a control means for controlling at least one parameter ofthe brewing device according to the signal. The presence of two coilsimproves the robustness of the recognition system with respect tophysical tolerances. Thus, the coding system can tolerate some variationin the positioning of the capsule within the brewing device, or in thepositioning of the conductive material with respect to the capsule. Thispermits recognition of coded capsules in a simple yet reliable mannerand reduces the time required to identify a particular capsule and/orincreases the accuracy of the identification.

Each resonant tank circuit comprises a coil and a capacitor, and isdesigned to resonate at a frequency that induces eddy currents in aconductive material. Preferably each tank circuit is designed toresonate at a frequency of 50 to 200 kHz, more preferably 75 to 150 kHz.Preferably the coils are spaced apart by a distance of from 40 to 50 mm,more preferably from 45 to 47 mm, because this corresponds to aconvenient capsule size.

Each electronic detection circuit monitors the change in coil impedanceand derives a signal indicative of the change in coil impedance. Furthercharacteristics of the signal may be extracted by electronic and/orsoftware processing. Since the amplitude of the signal is typicallyinversely proportional to the proximity of the conductive material tothe coil, preferably the coil and the conductive area are separated by adistance of 0 to 2 mm, more preferably 0 to 1 mm.

The conductive material may be part of, or attached to, the capsule, forexample the lid. However, in a preferred embodiment, the conductivematerial is releasably associated with the capsule. For example, theconductive material may comprise a metallic sheet comprising a centralopening shaped so as to releasably engage with the body part of thecapsule. Thus the conductive material may rest on or be attached to thecapsule holder, so that the capsule becomes associated with theconductive material when the capsule is inserted into the capsule holderof the brewing device. In this case, the lid need not compriseconductive material, and preferably consists of a non-conductivematerial, more preferably a plastic film.

Optionally, the device may also have means for allowing the user toadjust the parameters of the brewing operation, such as the brewingtime, the receptacle size etc. The means may suitably consist of buttonsor other inputs on the device, together with a control system.

The lid of the capsule needs to be opened or removed in order to releasethe tea material. Preferably the lid is opened automatically by thedevice after the capsule has been inserted into the capsule holder, e.g.as the upper rim of the capsule holder is connected to the bottom rim ofthe infusion chamber. Preferably, two openings are made in the lid, oneto introduce liquid into the capsule and the other to release liquid andtea material into the infusion chamber. However, because the capsuledoes not have a filter, there is no need to puncture or otherwise makean opening in the base of the capsule.

In a preferred embodiment, shown in FIG. 9, the lid is opened by pushingit against one or more static opening members when the capsule holdertravels upwards to connect with the bottom rim of the infusion chamber.The lid 32 is pushed against a static opening member 40 located on theinfusion chamber manifold 16. The function of the member is to create anopening in the lid in order to release liquid and tea material. This canbe achieved by a member with a sharp edge which cuts or punctures thelid. Alternatively, the lid may have pre-formed weaknesses, such asperforations 34 which reduce the force required to open it. In thiscase, the member 40 can be blunt, for example a wire. Preferably themember is angled or has a sloped part 41 so that as it moves into thecapsule, the flap formed by opening the lid is pushed away from theopening and held out of the way whilst the tea material is released fromthe capsule.

In the preferred embodiment shown in FIG. 9, a second opening forintroducing liquid into the capsule is made by pushing the lid against astatic needle 42 consisting of a tube with a pointed end. The needle 42pierces the lid. Water is then pumped from the reservoir to the heater,which is preferably a flow-though heater. The resulting hot water (andoptionally steam) is then pumped to the capsule and enters it throughthe needle. The influx of hot water pushes the tea material out from thecapsule through the opening made by the opening member 40 and into theinfusion chamber 10.

The heater and pump are controlled so that the target brew temperature(which is typically in the range 80° C. to 95° C.) is achieved in theinfusion chamber. Typically the water flow rate is in the range of 200to 400 ml/min, and the volume of water is 150 to 300 ml, depending onthe desired size of the beverage.

Preferably the infusion chamber 10 is made of transparent material suchas glass, or transparent plastic, so that the user can see the motion ofthe tea material (such as tea leaves) whilst the beverage is brewing.Most preferably, the infusion chamber is made of Tritan™ copolyesterbecause this material is transparent and has been found to have goodresistance to staining. Air may be pumped into the capsule holder 20(e.g. via the static needle) or directly into the infusion chamber 10 tocreate bubbles in the water and thereby agitate the tea material. Thisnot only enhances the visual appearance, but also aids infusion andhelps to prevent the tea material from sticking to the sides of theinfusion chamber. Moreover, the introduction of air releases aroma whichcan optionally be vented via a tube, which for example, has an outletnear to the dispensing spout or near the top of the infusion chamber,thereby providing the user with the aroma of tea during brewing. Thebrewing time, which typically ranges from 10 to 120 seconds, ispreferably set by user input and/or information read from the capsule.

Once brewing has taken place for the required time, the drain valve 21located in the base of the capsule holder 20 is opened, allowing thebeverage to drain from the infusion chamber. Preferably the opening ofthe drain valve is controlled automatically by the machine. The beverageflows from the infusion chamber through the filter 25 located in thecapsule holder below the capsule, through the passage 29, and finallyinto a cup 9 which the user has already placed onto the tray 8. Teamaterial is prevented from entering the cup 9 by the filter 25.

Optionally, there may be a dispensing spout 7 positioned beneath thecapsule holder as shown in FIG. 1, so that the beverage is dispensedthrough the drain valve and out through the spout. Thus, instead ofbeing dispensed vertically downwards into the receptacle, the beveragefollows an arc, similar to that of tea poured from the spout of a teapot. This enhances the “theatre” provided by the machine for the user,and also emphasizes the “tea-ness” of the beverage, as distinct fromcoffee making machines.

After the beverage has been dispensed, the spent tea material may berinsed from the wall of the brew chamber with further hot water.Preferably the rinsing water is introduced through rotating rinse jets18 located near the top of the infusion chamber. Better rinsing isachieved by rotating rinse jets than static ones. In a preferredembodiment, rinsing takes place immediately after the beverage has beendispensed, and the rinse water is also dispensed into the receptacle andbecomes part of the beverage. This removes the need for separatedisposal of the rinse water. In this case, the rinse water providesaround 15-30% of the total volume of the beverage, e.g. the volume ofrinse water used is around 50 ml.

Finally, after the beverage has been dispensed, the capsule holder islowered, preferably automatically, or alternatively by the user, forexample by activating a button. The user then removes the capsule holderfrom the support, using the handle 22, or in the second embodiment ofthe capsule holder shown in FIG. 6, the user may just remove thestrainer from the receptacle. The used capsule and spent tea leaves arethen disposed of, and the capsule holder can be rinsed. Since thecapsule holder is removable from the brewing device, it is easy toclean. The capsule holder is then returned to the support, ready for thenext use.

The device can be cleaned, for example by running a rinse cycle with notea material or by running a cycle with a cleaning material, for examplesodium percarbonate. The cleaning material can be provided in a capsule,or alternatively as a tablet which is simply placed in the capsuleholder.

The various features of the embodiments of the present inventionreferred to in individual sections above apply, as appropriate, to othersections mutatis mutandis. Consequently features specified in onesection may be combined with features specified in other sections asappropriate. Various modifications of the described modes for carryingout the invention which are apparent to those skilled in the relevantfields are intended to be within the scope of the following claims.

1. A capsule holder (20) for receiving a capsule (30) containing teamaterial, the capsule holder comprising: a sidewall (24) having an upperrim (23), means (28) for supporting the capsule within the capsuleholder, so that the capsule partially covers the area inside the upperrim, a filter (25) situated beneath the intended location of thecapsule, and an openable and closable passage (29) on the opposite sideof the filter from the upper rim.
 2. A capsule holder as claimed inclaim 1 wherein the sidewall is circular when viewed from above.
 3. Acapsule holder as claimed in claim 1 which further comprises means (71)for locating the capsule in its intended location in the capsule holder.4. A capsule holder as claimed in claim 1 wherein the means forsupporting the capsule also define one or more intended orientations ofthe capsule.
 5. A capsule holder as claimed in claim 1 wherein the meansfor supporting the capsule comprise one or more protrusions on theinside of the sidewall and/or the base of the capsule holder.
 6. Acapsule holder as claimed in claim 5 wherein the means for supportingthe capsule comprise a shelf on the inside of the sidewall of thecapsule holder.
 7. A capsule holder as claimed in claim 6 wherein themeans for supporting the capsule consist essentially of the shelf on theinside of the sidewall of the capsule holder.
 8. A capsule holder asclaimed in claim 5 wherein the means for supporting the capsule compriseribs, walls or pillars which extend upwards from the base.
 9. A capsuleholder as claimed in claim 5 wherein the base of the capsule holder isshaped so as to support the capsule.
 10. A capsule holder as claimed inclaim 1 which comprises a separable receptacle (70) and a strainer (72)in which the filter (25) is situated.
 11. A capsule holder as claimed inclaim 1 which contains a capsule.
 12. A capsule holder as claimed inclaim 11 wherein the capsule is adapted to correspond to the means forsupporting the capsule within the capsule holder.
 13. A strainer (72)which is adapted to co-operate with a receptacle (70) to form a capsuleholder (20) according to claim 10, the strainer comprising: a base (73)and a rim (74), means (28) for supporting a capsule (30) within thestrainer, so that the capsule partially covers the area inside the rim,and a filter (25) situated beneath the intended location of the capsule.14. The combination of a strainer (72) as claimed in claim 13 and acapsule (30) containing tea material.
 15. A capsule holder as claimed inclaim 1 or a strainer as claimed in claim 13 or claim 14 which comprisesconductive material having two edge sections which are located onopposite sides of the intended location of the cavity of the capsule.16. A capsule holder or a strainer as claimed in claim 15 wherein theconductive material comprises a metallic sheet comprising a centralopening shaped so as to releasably engage with the body part of thecapsule.
 17. A brewing device comprising an infusion chamber with abottom rim which defines an opening; a capsule holder as claimed inclaim 1; means for moving the capsule holder and/or the infusion chamberso that the upper rim of the capsule holder is connected to the bottomrim of the infusion chamber; means for introducing liquid into thecapsule so that the liquid and tea material can mix and flow into theinfusion chamber so as to brew the beverage; a valve for opening thepassage in the capsule holder to allow the beverage to flow from theinfusion chamber through the filter and out through the passage.
 18. Amethod of preparing a tea-based beverage in a brewing device as claimedin claim 17, the method comprising the steps of: a) inserting a capsulecontaining tea material into the capsule holder; b) connecting the upperrim of the capsule holder to the bottom rim of the infusion chamber; c)introducing liquid into the capsule and releasing the tea material fromthe capsule so that the liquid and tea material mix and flow into theinfusion chamber so as to brew the beverage; d) after brewing has takenplace, opening the passage in the capsule holder to allow the beverageto flow from the infusion chamber through the filter and out through thepassage.